Ship manoeuvrability is important for navigation safety. However, few studies have been specifically carried out for inland vessels. Since most of the empirical methods were generated based on databases of seagoing ships, the usability of these methods for inland vessels is doubtful. The objective of the present work is to assess the existing manoeuvrability models and find the most suitable ones for inland vessels. Furthermore, these models are integrated into a single new model that can predict the manoeuvring behaviour of benchmark inland vessels without extensive experimental tests. The method aims at inland ships of typical dimensions in the Yangtze River (inland ships on European waterways have different dimensions), which is characterised by a large water depth. After preselecting the most promising methods through reviewing literature, a selection of the empirical methods for hull forces and moments is performed by comparing simulation results to model-scale free-running experiments of various turning and zigzag manoeuvres. Considering the large variety of rudder configurations for inland vessels, this paper describes a procedure of using 2D open-water RANS results to calculate the rudder forces and moments. Accordingly, hydrodynamic coefficients of benchmark rudder profiles are provided to apply the proposed procedure for different rudder configurations.@en

The profile of a ship rudder influences the forces it generates, which in turn influence the manoeuvring performance of a ship. Thus, rudder forces and moments should be calculated considering the profile. Instead of an empirical estimation of the rudder normal force coefficient, this paper applies a RANS method to determine the hydrodynamic characteristics of various profiles, i.e. lift and drag coefficients. The RANS method is validated with a classic NACA 0012 profile and applied to 9 profiles from the NACA series, the wedge-tail series, and the IFS series. Furthermore, the 2D open-water RANS results are corrected for the effects of the propeller slipstream and the rudder aspect ratio. New regression formulas of the normal force coefficients are proposed for the tested profiles. These formulas are then integrated into a standard MMG model. Taking the KVLCC2 tanker as a reference ship, the manoeuvring model is validated with free-running tests executed by MARIN. Finally, the manoeuvring performance of the reference ship with various rudder profiles are quantified with turning and zigzag manoeuvres. The simulation results confirm that the wedge-tail series is most effective (largest manoeuvring forces) while the NACA series is most efficient (highest lift to drag ratio) among the tested profiles. The IFS series achieves a balance of effectiveness and efficiency.

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